Medics at NCIC are urging people who lost their sense of smell after contracting Coronavirus to seek help.
Smell retraining is one of the things that can help with anosmia – loss of sense of smell.
In May, Public Health England added anosmia to the official list of COVID-19 symptoms, falling in line with the World Health Organisation recommendations.
It is now known that of those people who develop COVID-19 that approximately half lose their sense of smell, so this is a significant problem with potentially a large impact on their quality of life.
Andrew Robson, ENT Consultant at NCIC, said: “It has been known for some time that viruses can cause anosmia, and this can last for considerable lengths of time. Anosmia also affects the sense of taste and is understandably quite distressing, affecting an individual's appreciation of food and drink among other pleasurable scents.
“This condition also potentially gives rise to dangerous situations, such as an inability to detect gas leaks, fire or spoilt food.”
There are many other causes of a reduced sense of smell, including allergies, sinus disease, nasal polyps and head injuries. The sense of smell often declines or disappears as part of the normal ageing process. SARS-CoV-2, the coronavirus responsible for COVID-19, is one of over 200 viruses to cause a loss of sense of smell, termed post-viral anosmia.
With other causes, where there is a physical obstruction leading to a blockage of the pathway to the nerve endings at the top of the nasal cavity, the symptoms may be reversed with treatment. However, it is believed that post-viral anosmia damages the nerve endings themselves, and for this there is no known cure. These nerve endings may recover over time, but this may be prolonged, and there is no guarantee of recovery.
In the majority – around 90 per cent - of cases the sense of smell recovers spontaneously after a COVID-19 infection.
The British Rhinology Society (BRS) and ENTUK, in light of COVID-19, published guidelines in August this year summarising how to manage a new loss of sense of smell. Unsurprisingly, it is recommended that in all new cases of new onset anosmia, a COVID-19 test should be obtained, if possible.
Anosmia does not need immediate attention from medical practitioners. There are no specific treatments recommended which will cure anosmia. The only treatment with some evidence for speeding up recovery is called "Olfactory training and support."
Olfactory refers to the sense of smell, and this is therefore another term for smell training. It is believed that the earlier this commences after symptoms start, the better the chance of recovery, and there is evidence to support this.
Christopher Rusius, ENT Registrar at NCIC, said: “A lot of patients have been to see their GP about their loss of smell. We are starting to see a few more patients referred to us now with that problem.
“Smell retraining is one of the things that can help. It involves buying a kit or making potions yourself with essential oils. The smells are quite strong and the thinking is that this can sometimes trigger the nerve endings to start stimulating again.”
In the UK, charities "AbScent" (www.abscent.org) and "Fifth Sense" (www.fifthsense.org.uk) offer advice and support for those with anosmia, along with smell retraining kits, and information on how to make your own.
It is thought that repeated exposure of the lining of the nose to smells (found in the essential oils in these kits) encourages the nerve endings to recover.
Mr Rusius added: “In light of the ongoing risk of coronavirus exposure, and the distress a resulting loss of sense of smell can cause, we would encourage early consideration of smell training in anyone for whom anosmia lasts for more than two weeks.
“In those who have lost their sense of smell, people should be aware that they may not be able to smell fire, gas or food that has gone off and take appropriate precautions.
“If anosmia lasts more than three months patients should be referred to the local ENT department.”
Fifth Sense www.fifthsense.org.uk